In case you missed the photo that started the rumors of Scoot McNairy playing a Barry Allen Flash in Zack Snyder's Batman V. Superman: Dawn of Justice, here it is again via Batman-News:
The green socks and crocs imply that McNairy's legs will be replaced in post production, leading to speculation that this the lower legs would be digitally sped up or blurred (though if you're talking replicating VFX blur, I'd use something striped because it gives you a really nice arc on video playback, but that's just me).
Now, The Devil's Eyes is reporting something they've heard from one of the extras on the film that sounds much more plausible, given our previous assumptions that Scoot McNairy would be Jimmy Olsen:
The extra states it like this: "Scoot is playing Jimmy Olsen, but with a bit of a twist. Jimmy was injured during the battle of Zod vs Superman. His legs where pinned under falling building rubble and that caused him to lose the legs. He now walks with the use of two prosthetic legs." The source goes on to add "He doesn't blame Superman for it [his loss of legs]. He feels grateful that Superman saved the world."
This lines up a bit more with the rumors we've been hearing about Batman V. Superman directly dealing with the consequences of The Battle of Metropolis and retroactively making the detractors from Man of Steel realize that film's climax had lasting repercussions.
Or that's the hope.
So, where's The Flash?